Internal-combustion engine



' Jan. 8, 1929.

1,697,876 w. MCHAR RY INTERNAL COMBUSTION ENGINE Filed Feb. 25, 1926 Patented Jan. 8, 1929.

series sraras WILLIAM MCHARR Y, OF CHELSEA, ENGLAND.

' INTERNAL-COMBUSTION E NGINE.

Application filed February 25, 1926, Serial No. 90,556, and. in Great Britain March 4, 1925.

My invention relates to two-stroke cycle internal combustion engines, and has for its object to provide an engine of this type which shall have higher volumetric efficiency than those at present in use.

A simple form of the invention is illustrated in the accompanying drawing.

The drawing is an end view partly in section of an eight-cylindered automobile engine, 1 arranged with two cylinders for each of four crankpins, the cylinders centersbeing atright angles to the crankshaft; The section shows the arrangement of the gear operating on the Y crankpin section, and the operations are precisely duplicated on the other three cranks.

The main casting A comprises the cylinders, the top half of the crankcase, and the bearings carrying the crankshaft B. C is the oil sump, partly shown. An L-shaped connecting rod D is reciprocated by the crankshaft B, and has a link E attached to its shorter end. A piston F is attached to the link E and is thereby reciprocated in a cylinder F, this cylinder functioning as a gas pump. A cylindrical valve G, reduced in di ameter at G, has the same motion as F, being connected to F so that although it has practically no end play it has a certain amount of lateral play. The valve G reciprocates in a hushed valve housing H, and H also serves to close the cylinder F. A cap J encloses the end of the valve G and is fixed to H. A piston K is attached to the longer end of D and reciprocates in acylinder K, this cylinder functioning as a working cylinder. A head L covers the cylinder K, and also carries the sparking plu which is not shown. M is an vexhaust maniold. There are four ports through which the charge passes, being: a piston-controlled port 1 through which the charge is entered into the pump; a valvecontrolled transfer port 2 which commences. in the cavity of F and passes across the valve housing H, terminating in the cavity of K;

which is open to the manifold M and a. valvecontrolled auxiliary exhaust port 4c, which "with the cylinder K a piston-controlled main exhaust port 3,

The operation of this engine is as follows,

comprising the passage of a charge through which is the state of affairs as illustrated. It

will be seen that the reduced diameter ofthe valve at G is about to register the port 2 and thus permit the charge to be transferred from the cylinder F to the cylinder K. The transfer continues until the piston K overruns the port 2, and the transfer is completed, the piston F being at about the end of its instroke. At the mo-' ment of the piston K overrunning the port 2 this piston has about another ten percent of its stroke to go to reach the end of the compression. Ignition is effected by any convenient means, and the piston K commences its outward power stroke. During the outstroke of the piston K on its uncovering the ports 2 and 4 respectively there is no lossas the valve G seals these ports. Towards the end of the outstroke of the piston K it uncovers the port 3 and the main exhaust takes place, until on its instroke the piston K overruns the port 3 and closes it. Following the main exhaust is theauxiliary exhaust which is caused by the valve G registering with the port 4, and this is continued until the valve G moves out of register withthe port 4, by which time the piston K has travelled about seventy per cent of its instroke. and immediately before the state of affairs illustrated.

At this point the passageof a charge. through the engine is complete.

I claim: The combination in a two-cycle internal combustion engine, of a compression cylinder and a power cylinder arranged side by side,

pistons in said cylinders; a tubular extension integral with the compressor piston; a dis- WILLIAM MOHARBY. 

